Lap yarn end cutting attachment for circular knitting machine



A Sept. 13, 1960 E. F. RATHER C 2,952,148

, LAP YARN END CUTTING ATTACHMENT FCR CIRCULAR NNITTINC MACHINE med April 2o, 1955 v l v4 sheets-sheet 1 v- INVENTOR ELME@ KAT/45 Mmm ATTORN Y5 sept. 13, 1960iA Filed April 20, 1955 E. F. RATHER LAP YARN END CUTTING ATTACHMENT FOR u J /zaw 74 24A (25H CIRCULAR KNITTING MACHINE 4 Sheets-Sheet 2 INVENTOR ATTOR Y5 i' v KUMWMQ Sept. 13, 1960 E. F. RATHER 2,952,148

, LAP YARN END CUTTING ATTACHMENT FOR v CIRCULAR KNITTING MACHINE Filed April 20, 1955 4 Sheets-Sheet 5 -i Ff" INVENTOR a MER E f4 r/#EK ATTORNEYS @29A y BY Sept. 13, 1960 E. F. RATHER 2,952,148

LAP YARN END CUTTING ATTACHMENT FOR CIRCULAR KNITTING MACHINE Filed April 20, 1955 4 Sheets-Sheet 4 lllllllmllll INVENTOR f2 MM E if? mfg ATToRNEYs n LAP YARN END yCUTTING A'I'IACI-IMENT FOR CIRCULAR KNITTING MACHINE 'Elmer F. Rather, Jackson, Mo., assignor, by mesne assignments, to Wayne Knitting Mills, Fort Wayne, Ind.,

a corporation of Indiana Filed Apr. 2o, 195s, ser. No. 502,623 11c1aims. (01.66-140) The present 4inventionprelates to lap yarn end cutting attachments for circular knitting machines and has for an object to provide an attachment for circular knitting VUnited States Patent() In the knitting of circular or seamless ladies hosiery' i prior to theinstant invention the lap yarns were cut by .l a stationary cutter. on the Vtransfer cap leaving a free end y from two to four inches n length which required subsequent removal by hand labor. After the stocking was knit it was taken from the machine land pulled over a for-rn mounted on rollers at which time it was visually inspected and the lform and stocking rolled until the lap f endsappeared at which time they were either manually cut by scissors or pneumatic clippers. This of course slowed down production by addition of this step and in- Y creased the cost by reason of the additional manual labor involved. Iln order to speed up the production cycle and reduce 'the cost per unit knit the present invention is now employed which removed this objectionable lap yarn end -.during thel knitting of the stocking or other fabric.

A lap yarn occurs-when a different yarn 4is yadded or .taken out of a seamless stocking and/or whenyarns .are changed. For instance, at the beginning of the body of the stocking, the shadow welt Vyarn or yarns are re- ,.moved andthe body yarn is inserted, each having a beginning or an ending end which extends several inches from the piecebeing knit. i The present invention provides an attachment which may be readily applied to the existing machine `in ad` dition tofthestationary cutter in a minimum of time, Aat a minimum of cost and which is rugged or durable Ain-,use'lending itself to a minimum of maintenance.

yWith the foregoing a'nd other objects in view, the invention will be more fully described herein-after, and will be more particularly pointed out inthe claims ap- Figure 1A is a side elevational view with parts broken away -and'parts shown in section of -the drive mechanism of the lap yarns cutter of Figure 1 in driving engagement taken at an enlarged scale.

Figure 2 is a perspective View of an outside transfer cam modified in accordance with the present invention.

Figure 3 is a fragmentary perspective view of a sece-fsnf?? t thetfnsfsf; can? effigie@ .2. .at .afi emerged.,

scale showing the placement of the stationary cutter blade.

lFigure 4 is a perspective View of a transfer cap having the rotary cutter of the present invention mounted thereon. Figure 5 is -a view :similar to Figure 3 showing the positioning of the two cutter blade members.

Figure 6 is lan exploded perspective view of the transfer cap and rotary cutter journal assembly.

Figure 7 is a top plan view of the transfer cap, yarn clamps and journal -assembly for the rotary cutter.

Figure 8 is an exploded perspective view of the rotary cutter tool, its drive and clutch mechanism.

Figure 9 is an exploded perspective view of a modifie for-m of Ythe present invention.

Figure :10 is a top plan assembled view of the form of the invention illustrated in Figure 9'. Figure l1 is a side elevational view of the form of th invention illustrated in Figure 9 in assembled condition. 1

Referring more particularly to the drawings and for the moment to the form of the invention illustratedin Figures l through 8, 20 designates a conventional latch ring having a cross 4arm 21 through which passes a bush 22 which is received into the bore of the hub 23 of the transfer cap 24. Secured to the underside of the transfer cap 214 is the outside transfer cam 25 beneath which is the rotatably driven dial 216 driven by the conventional dial spindle all of which to this point are well known and standard with all Scott-Williams circular knitting machines model K. The transfer cap 24 and transfer cam 25 for-m an assembly and with cross arm 21 and latch ring 20 are secured against rotary movement.

As shown in Figure 2 the transfer cam 25 is provided 4with a recess 28 opening into the periphery of the c'arn and receives, as shown in Figure 3, a lower stationary yarn severing means in the form of a cutter element or blade 29 which may be retained in place 4by screws 30'.

Cooperating with the stationary cutter 29 is a rotary cutter 31 which may consist of a shaft 32 having a cutting wheel comprising radially extending spike like teeth 33 having sharp cutting edges 34. The shaft 32 has a stepped down port-ion 35 and a flat portion 36, as best Vshown in Figure 8.

which is positioned in the path of a complemental projection 41 vsecured to the -under side of a clutch drum `42.

-The clutch drum 42 has a bore 43 therethrough having a flat vside-44 complemental in cross section tothe flat portion 36 of the rotary cutter shaft 32. The clutch drum 42 has two flanges 45, 46 which have a diameter slightly greater` than that of the drum 42. Between these'ang'es 45, 46 is received an operating fork yoke 47 of the drive -actuating mechanism. The yoke 47 is carried by an arm Vv48 `connected at its lower end tothe conventional shear vlever 58 and operated thereby. A bias leaf spring 49'is provided which ts over the top of the shaft 32 and bears Aagainstthe drum assembly-tending to keep it seated.

This leaf spring 49 is provided with a hole for receiving a screw or the like by means of which the spring 49 is secured to the yoke 4,7. Ak second spring 49 is secured 4 9' bersdreetly @the upper, end gf theshaftlso es .3 to exert va down pressure on the cutter 33 which is carried at the lower end of the shaft 32.

The dial spindle has an extension 50 to which is se- `toured a drive or head gear 51 having teeth engageable with the rotary cutter drive pinion 39.

`Secured to the hub 23 of the transfer cap 24 is a bracket 52 having a stub shaft 53 thereon for pivotally mounting two yarn clamps '4, 55. As shown in Figures l and 4 each clamp has a foot 56, 57 respectively for `engaging the yarn and holding same to the top of the transfer cap 24. Clamp 54 is connected to the conventional shear lever 58 which is connected to the conventional cutter 38 by rod 58A which is standard on all 'machines and is operated from the main cam drum of the machine vin a Imanner well known to this art. The relationship of the cutter 38 to the clamp is such that when shear lever 58 is actuated it moves cutter 38 and 'the cutter in turn lifts or rocks clamp 54. Clamp 55 is connected to a clamp actuating rod 59 which is actuated 'by a thrust rod 99 from the main cam `drum 100 of the machine in a conventional manner. As shown in Fig- I'ure 7 the two clamps 5'4, 55 are spaced from the yarn guides 60 in a direction eounterclockwise therefrom. .Clamp 54 is longer than clamp 55 and is first to engage the lap end. The bearing guide 37 for the rotary cutter is also arcuately removed from both clamps and the yarn .guides 60. The foot 57 of clamp 55 is about midway between the yarn guides 60 and the cutters 29, 31. This `relationship permits clamp 55 to retain the end of the yarn 61 when clamp 54 has released the yarn to hold the in-going yarn taut when -it is presented to the cutters 29, 31.

Referring to the modified form of the invention shown in Figures 9 et seq. the transfer cap 24A is provided Vwith a lslot 62 in registry with the recess 28A in the top of the outside transfer cam 215A. The transfer cam 25A is adapted to be secured to the under side of the transfer cap 24A. Secured in the recess 28A lof the cam 25A is a stationary cutter blade 29A the leading edge of which extends slightly beyond the periphery of the cam .-25A. Slidable over the cutter blade 29A and being horizontally reciprocable in the slot l62 of the transfer cap 24A is a movable cutter blade 32A hav-ing an upstanding screw `63 receivable in the drive yoke 64 of the drive arm 65 as best seen in Figure l0. The arm 65 has a bearing 66 receivable over a pivot post 67 carried by the transfer cap 24A and an oscillating yoke 68 adapted to receive and be driven by an eccentric 69 secured to drive shaft 70 which is journaled at its base in a bearing 37A secured to the top of the transfer cap The drive shaft 70 is journaled at its upper end in a bearing 71 secured to the cross arm 21A. A drive pro- .'jection 40A is secured to the shaft 70 and extends radially to be engaged by a projection 41A carried by drive v pinion 39A which is vertically shiftable and freely rotatable lover the upper end of shaft 70. The pinion 39A has a collar 71A having an annular groove'72 engageable `by an operating yoke 73. The yoke 73 is secured at its upperfend to an `operating rod 74. The rod 74 is biased to a raised position by spring 75 normallyelev'ating the drive pinion 39A out of driving engagement with the shaft 70. The lower end of the rod 74 is adapted to be :connected to the machine shear lever 58.

The dial spindle extension'50A has a head `gear 51A Vwhich drives the pinion 39A through suitable reduction gearing 76, 77.

As shown in Figure l0, the relationship between the yarn clamps 54A and 55A, cutters 29A, 32A and the yarn guides 60A are the same as that of the first form jo'f the invention, that is to say the clamp 55A holds the vin-going yarn taut while it is presented to the cutters Iwhen the clamp 54A has `released the yarn.

Inboth forms of the inventionthe two cutter-elements described are in addition to the conventional yarn end cutter 38 or 38A present on all machines of this type and the cutters of the present invention are so positioned as not to interfere with the normal knitting operation nor affect the yarn except to remove the lap end.

Assembly and `operation The lap yarn end cutter of Figures l through 8 may be assembled by first securing the stationary cutter blade 29 in the recess 28 of the outside transfer cam 25 and securing the cam 25 to the under side of the transfer cap 24. The bracket 52 is then secured tothe hub 23 of the transfer cap 24. The two yarn clamps 54, 55 are then pivotally mounted on the stub yshaft 53 of `bracket 52. The rotary cutter shaft 32 is inserted upwardly through the bottom of the bearing guide 37 `and the bearing guide 37 is secured to the top of the transfer cap 24 so that the rotary cutting head of shaft'32 will rest upon the lower stationary cutter blade 29 carried by the cam 25.

The transfer cap is secured to the latch ring assembly 20 in the conventional manner. The head gear 51 is secured to the extension 50 of the dial `spindle for rotation therewith after which the cutter shaft drive pinion 39 is slipped over shaft 32 `and intermeshed with the head gear 51. The yoke 47 is applied to the drum 42 between the flanges 45, `46 and the `drum 42 and the springr49 are applied over the upper end portion of the shaft 32 to bring the spring 49 into contact with the upper end of the shaft 32. 'Ihe arm `48 is then secured to the shear lever 58.

The yarn `61 is passed through the yarn guides 60 in the conventional manner and the yarn` ends are placed beneath the clamps 54, 55 on the transfer cap 24. The knitting operation is then begun in the conventional manner. All yarn :61 not in use is under both clamps 54, 55

' `and extends vfromthe yarn guides 60 beneath both clamps.

The incoming yarn or yarn to be knit into the work piece being knit is given slack by elevating clamp v54 which elevation is secured `through the action of shear lever 58. This slack permits the yarn to continue around the needle cylinder (not shown) over the outer top surface of the transfer cam 25 toward and on into the rotary cutter. Clamp 55 continues to hold the in-coming yarn until it has been cut. Clamp 55 is then raised by the control lever 59 through the rod 99 from the main cam drum 100. While clamp `55 is still in a raised position, the outgoing yarn is permitted to come under both clamps 54 and 55 and into the conventional cutter 38. This takes place while the out-going yarn (being attached to the fabric) is drawn around the circumference of the cylinder and into the new rotary cutter where it is cut within approximately one-half inch of the fabric. The rotary cutter lfirst cuts and the conventional cutter follows quickly thereafter. The actuation of the shear lever 58 Which opens cutter 38 and which cutter in turn rocks the clamp l54 simultaneously depresses the clutch drum 42, bringing the'drum projection 41 into driving engagement with the projection 40 of the drive pinion 39 thereby imparting rotation from the drive spindle extension 50 to the rotary cutter as shown in Figure 5 drawing .the yarn into the blades and cutting same. When this incoming yarn has been cut clamp 55 raises actuated by control lever 59 permitting the outgoing yarn to come under both clamps 54, 55, and into both conventional cutter 38 and rotary cutter 32 each of which cuts the out-coming yarn and produces a loose yarn end approximately 11/2 inches long between the two cutters. Both forms of this invention cut both the in-coming and the out-going yarns very near (one-half inch) the work piece whereas the conventional cutter cuts only the out-coming yarn. The yarn end which is attached to the yarn source or the one not attached to the fabric on this out-coming yarn produces the tail which is cut by this invention Ywhen -f-piece being knit..

piece and not two to four inches therefrom as is presently done by the conventional yarn cutter 38,on,all transfer caps. v

The clutch drum driving arrangement is employed to cut down the wear between the stationary cutter blade Z9 vcarried by the transfer cam 2'5 and the rotary cutting head of shaft'32, for while the stationary blade 29 acts as an end thrust plate or bearing for the shaft 32 wear can be Ireduced to a minimumbyrotating the shaft 32 only when :yarn is being fed into orv taken out of the work Referring now to the form of the invention shown in Figures 9 through 11, the stationary cutter blade 29A is secured in recess 28A of the outside transfer cam 25A and the cam 25A is secured to the under side of the transfer cap 24A. The bearing guide 37A is then secured in place on the top of the transfer cap 24A. The drive shaft 70 is then passed through the bearing block 71 which block is then secured to the cross arm 21A inserting the base of shaft 70 into the bearing guide 37A. 'Ihe clutch pinion 39A is then passed over the top of the shaft and the yoke 73 is placed in the groove 72 of the pinion collar 71A. The yoke 73 is then connected to the operating rod 74 which in turn is secured to the shear lever 58.

The movable cutting blade mechanism is then set in place by placing the bea-ring 66 of arm 65 over the pivot post 67 of the transfer cap 24A so that the eccentric 69 enters the yoke 68. The upstanding screw 63 carried by the movable blade 32A is then passed through the slot 63A in the spring 63B and enters the yoke 64 whereby upon rotation of shaft 70 the blade 32A will be reciprocated. The leaf spring is between the top of blade 32A and yoke 64 to urge the two cutting blades 29A, 32A into contactual engagement. rIlhe pinion drive is adapted to be engaged with the head gear 51A through suitable reduction gearing. The speed of reciprocation of blade 32A can be controlled by the selection of the reduction gears.

In the manner above described with respect to the first form of the invention, as the yarn is fed into and out of the workpiece being knit with the elevation of clamp 54A and depression of the shear lever 58 the rod 74, and yoke 73 will bring the pinion 39A into driving engagement with the shaft 70 rotating same causing the eccentric 69 through yokes 68 and 64 to impart a reciprocating drive to the upper cutter blade 32A whereby the yarn riding over the top outer surface of the transfer cam 25A will be presented to the cutting blades 29A and 32A shearing the yarn proximate the workpiece being knit.

Although I have disclosed herein the best forms of the invention known to me at this time, I reserve the right to all such modications and changes as may come Within the scope of the following claims.

What is claimed is:

1. A lap yarn end cutter for a circular knitting machine having a dial driven by a rotary spindle comprising a pair of cutting elements, positioning means adapted to be operatively associated with said machine and cutting elements to position said cutting elements proximate the Work to be knit and adapted to be positioned to engage and cut the lap yarn ends fed into and out of the work piece to be knit, clamp means operatively associated with said positioning and cutting means and being located so as to receive the incoming and outgoing lap yarn ends and clamp same to said positioning means whereby said lap yarn ends are presented to said cutting elements under tension to facilitate their being cut, and selective drive means adapted to be operatively associated with the rotary spindle of said machine and one of said cut- ,ting elements to 'impart relative cutting movement between said cutting elements only when a lap end is fedinto or Vout of the work piece to be knit. n 12. A lap yarn end cutter for a circular knitting machine comprising an outside transfer cam having a recess therein opening to the periphery thereof, said cam being adapt- Y. ed to be secured to the machine transfer cap, a stationary cutter'blade secured in the recess of said cam and exltending slightly beyond the periphery of said cam, a

toothed headed rotary cutter having a shaft and being adapted to be positioned with the toothed head against and rotated upon said stationary cutter blade, journal means for said rotary cutter shaft adapted to be secured to said transfer cap, and drive Ymeans on said rotary cutter adaptedto be drivenfrom the machine drive to impart rotary motion to said rotary cutter.

3. A lap yarn end cutter as claimed in claim 2 further comprising clutch means on the shaft of said rotary cutter and being adapted to selectively engage the drive means on said shaft with the drive of said machine to compel rotation of said rotary cutter.

4. A lap yarn end cutter for a circular knitting machine having a dial and a drive mechanism therefor comprising an outside transfer cam having a recess therein opening to the periphery thereof, s-aid cam being adapted to be secured to the machine transfer cap, a stationary cutter blade secured in said recess and extending slightly beyond the periphery of said cam, a movable cutter blade receivable in said recsss and being movable over and upon said stationary blade, reciprocating means adapted to be operatively associated With said movable cutter blade and transfer cap for imparting a recipro catory motion to said movable blade along the major axis of said slot, and drive means adapted to be carried by said transfer cap and being operatively associated with said reciprocating means and the drive mechanism of the dial of said machine to impart a driving motion from the machine to the movable cutter blade for cutting lap yarn ends.

5. A lap yarn end cutter for a circular knitting machine as claimed in claim 4 further comprising clutch means operatively associated with said drive means for selectively driving said reciprocating means and movable cutter blade.

6. Yarn clamping and severing mechanism for a crcular knitting machine having a rotating cylinder with a complement of needles, a stationarily-supported retractable yarn feeding finger, and a stationary disk axially within the needle circle at the top of the cylinder, said mechanism including a vertical axis cutting Wheel disposed substantially rdiametrically opposite the yarn feeding finger and rotatively supported adjacent the periphery of the disk with the ends of its blades sweeping beyond the disk periphery into close proximity to the needle circle; a cooperative cutting edge at the bottom of the disk; and a retractable clamp element positioned on the disk in the interval between the yarn feeding iinger and the cutting wheel beneath which, upon each retractionk or re-insertion of the iinger from or to feeding position, the yarn is drawn by rotation of the cylinder Incident to being brought into the range of the cutting wheel for severance by the latter close to the needle circle.

7. A lap yarn end cutter for a circular knitting machine comprising a transfer cap and cam assembly, a stationary yarn severing means carried by said assembly, a rotatable cutting wheel having teeth extending from the periphery thereof with the teeth in operative cutting relationship against said stationary yarn severing means, and drive means for said rotary cutter adapted to be driven from the machine drive to impart rotary motion to said rotary cutter.

8. A lap yarn end cutter as claimed in claim 7 further comprising yarn clamping means carried by said assembly "7 located on said assembly adjacent said yarn severing means.

9. A lap yarn end cutter as Claimed in claim 7 Where- -in said rotatable cutting Wheel rotates about a Vertical axis.

1'0. A lap yarn end cutter as claimed in claim 7 Wherein said rotatable cutting wheel and said stationary severing means are located on said cap assembly in yarn severing relationship proximate the periphery of said cap.

11. A lap yarn end cutter for a circular knitting machine compr-ising a transfer cap assembly, at least two cutting members associated together to constitute yarn severing means, one at least of said members being a rotatable cutting wheel having teeth about its periphery in operative cutting relationship with the other member, y15 2,713,254

ends approximately vat .the tubularfabric beingr knitted.

References nCited Vin the tile of this patent UNITED STATES PATENTS 1,382,958 Scott Oct. 29, 1918 1,863,720 Lawson et al. June 21, 1932 2,295,450 Cole Sept. 8, 1942 2,375,473 Holmes .et al. May 8, 1945 2,667,053 St. Pierre et al. Jan. 26, 19,54 2,669,765 Auton Feb. `23, 1954 Minton July 19, 1955 

